German Pat. No. 29 17 060 describes a method for solidifying tritium water. A minimum density of 0.3 grams/cm.sup.3 is a boundary condition for the product to be cured. The basis for the formulation used in the above reference is a mixture of cement, bentonite and tritium water. The method described and the product correspond to laboratory experiments.
An attempt was made to produce a product for terminally storing tritium water on the basis of the formulation of the above-mentioned German Pat. No. 29 17 060. When translating this mixture developed in the laboratory to a semi-technical scale (university experiments and in the technical scale of 1:1), it was shown however that the terminal storage of the tritium water is not possible because the requirements imposed on large containers having an interior volume of approximately 8 m.sup.3 could not be fulfilled. These requirements include a solid product having the highest possible water content and no residual water. All large specimens which were produced having a water content of more than 60% by weight have residual water during and after curing. Such an occurrence is not permissible for the terminal storage, for example, in a terminal storage mine according to the requirements of the authorities empowered to grant a permit for this purpose.
On the other hand, a content of water below 60% is not worthwhile in view of economic considerations.